Interleukin-4 (IL-4, also known as B cell stimulating factor or BSF-1) was originally characterized by its ability to stimulate the proliferation of B cells in response to low concentrations of antibodies directed to surface immunoglobulin. IL-4 has been shown to possess a broad spectrum of biological activities, including growth stimulation of T cells, mast cells, granulocytes, megakaryocytes and erythrocytes. IL-4 induces the expression of class II major histocompatibility complex molecules in resting B cells, and enhances the secretion of IgE and IgG1 isotypes by stimulated B cells.
The biological activities of IL-4 are mediated by specific cell surface receptors for IL-4. Human IL-4 receptor alpha (hIL-4R) (SEQ ID NO:1) is described in, for example, U.S. Pat. Nos. 5,599,905, 5,767,065, and 5,840,869. Antibodies to hIL-4R are described in U.S. Pat. Nos. 5,717,072 and 7,186,809.
Methods to produce antibodies useful as human therapeutics include generating chimeric antibodies and humanized antibodies (see, for example, U.S. Pat. No. 6,949,245). See, for example, WO 94/02602 (Abgenix) and U.S. Pat. No. 6,596,541 (Regeneron Pharmaceuticals) (both of which publications are herein specifically incorporated by reference) describing methods of generating nonhuman transgenic mice capable of producing human antibodies.
Methods for using antibodies to hIL-4R are described in U.S. Pat. Nos. 5,714,146; 5,985,280; and 6,716,587.